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24 - Electrical System
Located below the left side of the floor panel are two power
relays (K2 & K3) These are connected directly to the
battery and supply high-energy power to the power module
and the drive controller These relays are controlled by the
module for which they provide power, but are wired slightly
different
One side of the K2 power relay coil is connected to battery
power, and the Power Module activates the relay by pulling
the other connection to ground
Both sides of the K3 drive relay are connected to the drive
controller The positive side is kind of like an enable circuit
that enables both the K3 relay and the brake release
However, the negative side of the two are controlled
separately
Low Voltage Cutout
The main machine controller is equipped with a low-voltage cutout feature to prevent over-discharging of the
batteries. When the battery voltage falls below a defined threshold, some machine functions are disabled.
These threshold values are dependant on the type of battery specified in the main controller. In the first
stage of cutout, the scrub system is disabled, but the recovery system will remain active At the second stage,
even the recovery system will be disabled, but the drive system remains active
The drive controller has its own cutback feature, separate from the main controller When the drive
controller senses battery voltage too low, it will reduce power output to the drive motor to protect the
battery
Cutout Level
Threshold-Wet
Threshold-AGM
Affected Systems
Stage 1
30.8
32.6
All scrub functions disabled
Stage 2
30.6
32.4
Both scrub and recovery disabled
K2 Power
Relay
K3 Drive
Relay
Battery
Cable
Power
Jumper
